As described in connection with Patent Literature (PTL) 1, a battery pack of this type has a battery assembly in which a plurality of battery cells are arranged in such a manner that positive electrodes and negative electrodes of the battery cells adjoin each other and serially interconnecting and bundling the positive electrodes and the negative electrodes of the adjoining battery cells by conductors referred to as busbars. The battery assembly is used while being contained in a housing as necessary. A positive electrode (hereinafter called a “total positive electrode”) and a negative electrode (hereinafter called a “total negative electrode”) of battery cells at both ends of the battery assembly work as DC outputs of the battery pack.
In a battery pack, a battery control unit for controlling the battery assembly is sometimes provided at end portion of the battery assembly in a direction where the battery cells are aligned. The battery control unit has, for instance, a current sensor for detecting an electric current output from a battery pack, a precharge contactor, a main contactor, and others. The battery control unit is used while the total electrode terminals, or the total positive terminal and the total negative terminal of the battery assembly, are connected to a controller of a load by way of the battery control unit.